Add architecture comments to content-editor.tsx, markdown-paste.ts,
extensions/index.ts, mention-view.tsx, content-editor.css, and
preprocess.ts explaining: why single markdown pipeline, why
data-pm-slice for paste detection, typography benchmarks, mention
card sizing rationale, and what was removed from the old system.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Replace three divergent data paths (Marked HTML loading, regex post-processing
saving, separate paste parsing) with one symmetric path through @tiptap/markdown.
Key changes:
- Create features/editor/ module with ContentEditor (unified edit+readonly)
and TitleEditor, replacing components/common/ editor files
- Load content via contentType: 'markdown' instead of markdownToHtml() hack
- Save content via editor.getMarkdown() directly, no post-processing
- Merge RichTextEditor + ReadonlyEditor into single ContentEditor with
editable prop
- Extract extensions into separate modules (mention, file-upload,
markdown-paste, submit-shortcut, code-block-view)
- Extract shared preprocessMentionShortcodes to components/markdown/mentions.ts
- Add copyMarkdown utility for clipboard operations
- Upgrade all @tiptap packages from 3.20.5 to 3.22.1 (lexer isolation fix,
HTML entity roundtrip fix, table alignment support)
- Delete markdownToHtml.ts, readonly-editor.tsx, and 10 old component files
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>